Volatile Products Formed by Curie-Point Pyrolysis of Chlorodeoxycellulose

Abstract

Curie-point pyrolysis of chlorodeoxycellulose (Cell-Cl) samples prepared from microcrystalline cellulose with N-chlorosuccinimide and triphenyphosphine in LiCl/N, N-dimethylacetamide under homogeneous conditions, is studied by gas chromatography (GC) and GC-mass spectrometry. Chlorine-containing pyrolytic products obtained by pyrolysis of Cell-Cl samples with degrees of substitution (DS) between 0.33 and 1.59 at 590°C for 4 sec are hydrogen chloride, chloromethane, chloroethane, vinyl chloride, and chloroacetoaldehyde. Another chlorine-containing product, which is formed only from Cell-Cl samples with DS higher than 1.2, is 5-chloromethyl-2-furaldehyde. Effect of pyrolytic temperature on the pyrolytic behaviour of cellulose and Cell-Cl with DS of 0.81 is studied at four levels of temperature between 385 and 764°C. Cellulose gives only carbon dioxide and 2-furaldehyde when pyrolyzed at 385°C, while Cell-Cl with DS of 0.81 gives 13 non-chlorine products. The numbers of pyrolysis products formed from cellulose and Cell-Cl reach their maxima at 590°C . The total GC peak area of cellulose increases linearly with raising pyrolvsis temperature while that of the Cell-Cl reaches the maximum at 590°C.